A free hand

After almost 60 years in the business, Quentin Blake is one of Britain's - perhaps the world's - best-loved illustrators. He tells Stuart Jeffries about working with Roald Dahl, the teacher who got him started, and the hardest job he ever had to do

Dusk is settling beyond the vast picture windows of Quentin Blake's studio in a west London mansion block, as the illustrator ushers me to a well-worn Eames chair so I can sit and watch how he works. The man the Guardian once described as "a national institution" (which makes him sound like a cross between the Queen and Broadmoor) begins each morning at 9.30 at the guillotine, chopping sheets of paper into shape to warm up for the day ahead. He stands to draw, working on a light box. The glow from it gives him the aura of a magician. Some interviewers have described him as gnome-like, but I won't.

He puts a rough drawing on the light box and on top of that a sheet of watercolour paper. He then draws with old-fashioned dip pens, or sometimes a vulture quill. What he does is not, he stresses, tracing. "It's important that I can't see the rough drawing underneath too clearly, because when I draw I try to draw as if for the first time; but I can do it with increased concentration, because the drawing underneath lets me know all the elements that have to appear and exactly where they have to be placed." When the drawing is done, he swivels round to a nearby desk where he sits to paint.

Is there anything he can't draw? "I stay away from motor cars. And I can't do architectural drawings, really. What I want to convey is movement and gesture and atmosphere. I like drawing anything that is doing something. Dragons are good because you can arrange them in interesting ways across the page, get people to ride on them. I can't seem to keep birds out of my books." You can see them not only in his edition of Aristophanes' The Birds and his book with John Yeoman called Featherbrains, but in a grinning self-portrait featuring him dangling from a ceiling fan, pencils stuffed in his pockets, papers and birds flapping round. His grin is the still centre to the chaos.

I ask Blake what was the most difficult drawing he did and he tells me it was the one where he had to depict the writer Michael Rosen grinning, even though he was really feeling very sad. "I did it 15 times, but I just couldn't get it right," he says. "It wasn't so much that he was sad. I could have done that. It was that he was sad, but trying to look happy. I did it once and he looked too cheerful. Another in which he looked too sad. It was a matter of trying to dose the happiness."

Even to the illustrator whose visual genius determined how Willy Wonka, the Big Friendly Giant, Matilda and a host of other fictional characters looked to millions of people around the world, this wasn't a small matter. He may have had six decades of work and 300 books behind him, from Kingsley Amis's Lucky Jim to the best part of Roald Dahl. He may have drawn for Punch and the Spectator, taught illustration at the Royal College of Art and earned an OBE in 1988. But nothing in Blake's oeuvre up to that point was so fraught, so emotionally poised as this.

Blake's image was to be first in Rosen's Sad Book, in which our current children's laureate wrote of his grief at the death of his 18-year-old son, Eddie, from meningitis. This wasn't going to be a normal children's book (if there is such a thing). The words accompanying Blake's illustration were to read simply: "This is me being sad. Maybe you think I'm happy in this picture. Really I'm sad but pretending I'm happy."

"My illustration had to say that he was smiling because he thinks people won't be able to tolerate his grief," says Blake. "It had to show him smiling while looking stressed. I got it in the end." If you look at the published image carefully, it finally dawns that Rosen's smile is forced. Just around the corners of the mouth, there is a hint of a grimace. The lower lip too twisted to be joyful. The eyes almost wild.

Rosen had sent the text to his publisher along with the uncertain note: "Is this is a book?" They weren't sure: "His editors sent the text on to me, saying, 'We don't know if we can publish this, but would you like to have a look at it?' What I looked at was really two pages of text, wonderfully written, and it was clear there was a whole book in there, but it needed illustrating. And clearly Michael intended it to be illustrated because he had written it with changes in mood every two sentences that cried out for illustrations. I really wanted to help it."

So Blake, standing at the desk in his studio in the Kensington mansion block where he has worked for more than 30 years, went to work. What he drew made Rosen's words a book. Next to the words, "What makes me most sad is when I think about my son Eddie. He died," Blake did a gloomy portrait, all grey wash and black lines. "The way I drew his eyes for that image - well, they're really just scrawls." And yet the scrawls suggest so much: sleepless nights, tears, a world of grief. "You can't draw that way slowly. I could have done them anatomically correctly, with eyelashes and so on, but I didn't want to. I tend to do everything fast." Why? "If you're playing tennis and you throw a ball in the air very slowly and sweep your racquet slowly, you're not going to produce a good serve."

Then Blake's palette lightens the mood, in an octet of cheerful scenes from Eddie's life. But the text is grim: the narrator admits that thinking of Eddie's death makes him angry ("How dare he go and die like that? How dare he make me sad?"). The eighth panel, the most harrowing of the lot, was the easiest work for Blake: it is empty.

When the book came out in 2004, the critic Dina Rabinovitch wrote: "It is an outstanding book, head and shoulders over anything else, for any age, published this year." Blake says: "It was a very moving experience to do it, and commercially it did well because there aren't many books like that."

The book struck powerful chords, especially among bereaved parents and siblings. One parent submitted this review to Amazon: "Ever since my daughter died I've been trying to find ways of telling my autistic son about her. I said all the usual stuff, but he became inconsolable and cried as if heartbroken. I've left it alone for months and then suddenly found this book. I knew it would be perfect for him, as he has such a visual intelligence. It was. He asked me to read it again and again and pointed out aspects of the pictures that I had failed to notice."

Blake has agreed to this rare interview because he wants to promote the Big Draw, an annual festival of which he is patron. This year it will include 1,300 events across the country aimed at encouraging people to draw. Why is it that he can draw and I can't, damn him, I ask the 74-year-old doyen of British illustrators. "Sorry!" he replies. I notice he's done a book called Drawing for the Artistically Undiscovered ("100% klutz certified"), which might help me redress the balance.

By way of a longer answer, Blake relates his early career. "There was nothing to suggest that I could draw - my parents certainly couldn't." He started drawing young, probably about the age of five. It proved an astute career move: Blake has always earned his living from drawing. "I remember a visitor during the war saying, 'He draws a lot, but he won't speak!'" What did you draw? "I was particularly motivated by things that were funny. But not entirely. I remember when I was 11 or 12 doing a realistic drawing of boys after a football match in the changing room. Heaven knows why, I hated football!"

But it was the husband of Mrs Jackson, his Latin teacher at Chislehurst and Sidcup grammar school, who shaped Blake's career when he was 15. "He was a painter, who had a very naive style influenced by Modigliani. What I loved about him was that he spoke both about Punch and Michelangelo. So I showed him my drawings. " Better yet, Alf Jackson encouraged young Blake to send some drawings to Punch. Most were rejected, but eventually, aged only 16, he got published.

In Blake's 2000 memoir Words and Pictures, there is a reproduction of the precocious cartoon that Punch published before he was out of his teens. A bearded beatnik with a paintbrush in one hand drips juice from a pear he is holding on to a canvas. It's an accomplished, warm-hearted Jackson Pollock satire (even then there was nothing caustic in Blake's work). "They paid me seven guineas! I didn't know what to do with it - I didn't even have a bank account."

Instead of going to art school or trying to live off his art, he went to Cambridge in 1953 to read English. Why? "I knew I wanted to be an artist and that I would have to train, but I thought that if I went to art school I would never go to a university, whereas if I did go to university I would still have the option of doing art." The iconoclastic don FR Leavis, whom Blake would gently satirise in drawings, was one of his tutors, and his then unfashionable enthusiasm for Dickens infected Blake. "I was fascinated by Dickens and by his illustrators, who were crucial to his career as a novelist. I've never lost my interest, nor my love, for Cruikshank and Phiz, Dickens' illustrators." In 1995, he did an illustrated version of A Christmas Carol.

At Cambridge, he also dabbled in illustrating for magazines, art editing some issues of Granta (though before it became the globally renowned literary journal it is today). He was asked to draw for the university magazine Varsity, but refused because the editor, Michael Winner, was turning it into "something like the Daily Mirror".

Already, Blake could pick and choose among the offers of work. Not only was he working for Punch, but, during his national service, he finished his first book. English Parade was for soldiers who hadn't mastered reading. "From time to time I had to show my work to a lieutenant-colonel for his approval," he recalls. "A few moments of silence and then: 'Very good, Sergeant Blake. But the grass in this one ought to be shorter.' 'Yes, sir. I'll see to it, sir.' The problem with making the grass shorter in drawings is that you can't cut it: you have to do the drawing again. But at least it was preparation for encounters with editors and - worse - committees, later on."

After Cambridge, Blake tried to make a living from art. "I decided to give it until I was 30 and if I hadn't made it by then, pack up and do something else." He went to Chelsea School of Art. "I went there because I read an article about a man called Brian Robb who described himself as cartoonist, painter, illustrator. I wanted to be all three! I'd seen his illustrations to Tristram Shandy and I thought he could give me the advice I needed. He did. It was wonderful to know, almost instinctively, what was the right thing to do to help make one's dream a reality."

Blake dutifully attended life drawing classes (there are some rather lovely life drawings from the time in Words and Pictures), and mastered the skill of looking at something really hard that Robb instilled in him. "But that isn't how I work now. In life drawing, one was obsessed with capturing accurately what one saw, but that isn't enough for art. The really great artists like Rembrandt and Goya could draw what was in front of them and unleash their imaginations at the same time. I couldn't. So now I don't draw from life. I draw as though I'm trying to capture something that isn't there."

Inventing new worlds rather than capturing pre-existing ones has been Blake's forte: "Some people have vivid memories of childhood - Michael Rosen's recall is astonishing - but I don't; I just try to invent it again now, whether it is a child or a dog or a woman reading a book or a hunchback of Notre Dame."

Is this why he became a book illustrator, so he could invent visual worlds? "I think so. Certainly, when I asked my friend John Yeoman in 1960 to write a book so I could do pictures for it, that is what I had in mind."

His association with Yeoman, an old school friend who went up to Cambridge with Blake in 1953, has been the longest creative partnership in his life: they still regularly collaborate on books together. More than that, they share another flat in the same block as Blake's studio.

Did Blake never want to be a cartoonist? "No. I didn't really want to spend much time thinking about politics." Instead, as he writes in Words and Pictures: "When I took my first steps in book illustration, I found that I had entered a sort of enchanted grove where there were things to draw at every turn." In 1960, he illustrated his first children's book, Yeoman's A Drink of Water. "I had asked him to write a story I could illustrate. I usually rely on other people to invent the stories, because I can't be bothered with the words."

That grove became even more enchanting when, in 1975, he was asked to illustrate for Roald Dahl. Was he the irascible old monster that others have described? "No, I was very fond of him, though he could be curmudgeonly. Initially, I was very nervous of him because he was so powerful. He did like to tease me for my white plimsolls, and he was the only person to call me Quent. He would say: 'Here's Quent, going out for dinner in his plimsolls.'" I glance at Blake's feet: he's still wearing white plimsolls in defiance of Dahl's satire.

It was the schematic yet potent illustrations that Blake did for Dahl's stories for the next 15 years until the writer's death that, for many, were his iconic works. "What was so wonderful to me was that so many of Roald's stories were fantastical, unrealistic, so I was free to do what I wanted. I could let my style develop. Think of The Twits or the BFG - they don't really take place in a realistic world. They come from my head." That said, Dahl sent Blake a dirty old pair of sandals through the post and suggested he use them as models for The Big Friendly Giant's footwear. He did.

Was there a danger that he might become so synonymous with Dahl that he could illustrate for nobody else? "Apparently not. I've worked with lots of writers - Russell Hoban, Joan Aiken, Michael Rosen. I find I do little shifts, not just between writers, but between books by the same writer, to give each work its identity."

Isn't he locked in an infantile world? For the first and last moment in the interview, Blake looks a little cross. "Not at all. I've done illustrations for Quixote, Cyrano de Bergerac, French writers like Daniel Pennac. All adult stuff. Let me show you my latest book." Called Vivre Nos Vieux Jours!, it is a book showing what old people can do. It is an expanded version of the drawings Blake did of elderly patients at a health centre in Kensington "As you can see, I put old people in trees a lot."

In France, where he spends much of the year and was made a Chevalier des Arts et des Lettres by the French government for services to literature in 2004, they created an imprint, Gallimard Vieillesse (Gallimard Old Age), for this book, which will be published next month. He hopes it will be published in English soon.

"I'm doing a lot for the NHS now." He shows me a photo of a mural called Planet Zog that he's done for a health centre in Harrow. It's in the waiting room, to make the experience for children less grim. In Blake's version of the public health system , some of our NHS problems seem to have been solved by recruiting aliens. If only Patricia Hewitt had listened to him. "It might be nicer to have your trolley pushed by someone with eight legs, don't you think?" It is a gentler, barmier world than the one we know - like many of Blake's works, it has the helpful effect of cheering you up.

After the interview, I walk from his flat realising that my picture of Blake is incomplete. (I also realise that I have forgotten to tell him my hilarious anecdote about when a waiter in an Indian restaurant asked me how I would like my dal soup and I replied: "Rolled." True story.) Seduced by Blake's art, I forgot to ask about his personal life. Is he gay, straight, what did his parents do, does he have children of his own, nieces or nephews to enchant with his charming illustrations? All I do know is that he was nicknamed Q when he taught at the Royal College of Art. I'm especially intrigued because Blake has done many interviews, without shedding any light on what he gets up to outside the studio.

The following day Blake is too busy drawing to speak to me, but sends an email to this intrusive hack: "I don't have anything interesting to conceal or reveal in my private life, and it is really only my work and professional life that I want to talk about." Fair enough. "I think the relevant item here is that I have not been married or had children, so that I tend to approach the subject of children's books as a teacher rather than a parent. In other words, I try to identify with the children in the books rather than look upon them as a benevolent adult."

I'm not very sure about this answer (does a teacher identify with children?), but still, one can see that image of the benevolent adult that is Blake again and again in his work. There he is on G2's cover, in a shadow of grey wash, quite possibly wearing his rebellious white plimsolls. He's encircled by smiling children and characters he has created over a happy lifetime's work. It reminds me of Robert Buss's painting Dickens' Dream, where the author is surrounded by his creations. Here we can see some of the characters Blake put before our eyes. They are (clockwise from the top): Up With Birds by John Yeoman; Quentin Blake et les Demoiselles des Bords de Seine; How Tom Beat Captain Najork by Russell Hoban; Clown; Michael Rosen's Sad Book; The Life of Birds; Mrs Armitage on Wheels and The BFG by Roald Dahl.

And, at the centre of the picture, typically, is Blake's smile. It is gentle, without the hint of a grimace. It is his signature, in life as in art. But when I saw him, he wasn't that stubbly.